Adds a simple property test to the `clist` package. This test uses the [rapid](https://github.com/flyingmutant/rapid) library and works by modeling the internal clist as a simple array.
Follow up from this mornings workshop with the Regen team.
## Description
Internalize some libs. This reduces the amount ot public API tendermint is supporting. The moved libraries are mainly ones that are used within Tendermint-core.
